The National Inventory of Architectural Heritage was established to identify, record and evaluate the architectural heritage of the country in a systematic and uniform manner. Each county inventory is published in a full-colour, attractively illustrated booklet in English and Irish introducing the architectural highlights of the area, and includes a free, searchable CD containing a database, with descriptive text and photographs, and relevant mapping.

The wealth of Carlow's agricultural production encouraged not only a range of substantial farms and larger country houses but also a rich legacy of agriculture-related buildings. These range from farm and stable buildings to impressively scaled mills and warehouses. Carlow's transport heritage is also an important contributing factor to its particular character. The county boasts a range of 18th-century canal structures along the River Barrington, as well as 19th-century railway architecture. However, domestic architecture, large and small, is closest to the people and reflects most especially the history of Carlow over the centuries.